Wartook Reservoir is located on the MacKenzie River in the central Grampians. It is the primary source of supply for Horsham and Natimuk, and a secondary source for Supply System 6 of the Wimmera Mallee Pipeline. The reservoir, which has a high recreational value, also provides important flows to the environment.
​Recreational fishing is popular at this lake.
Dogs are not permitted.
​Boating speed limit is 5 knots.
Swimming, water skiing, jet skis and camping are not permitted.
Duck shooting is not permitted.
Camping is not permitted.
| Current Level | 438.900 m AHD |
| Current Volume | 7,780 ML |
| Percent Full | 27% |
| Current Inflows | 150 ML/week |
| Current Airspace | 21,520 ML |
| Full Supply Level | 441.68 m AHD |
| Full Supply Volume | 29,300 ML |
| Maximum Operating Volume | 29,300 ML |
| Spillway Level | 441.83 m AHD |
| Spillway Length | 175 m |
| Spillway Capacity | 1,500 ML/day |
| Secondary Spillway Level | 442.10 m AHD |
| Secondary Spillway Length | 127 m |
| Secondary Spillway Capacity | 25,056 ML/day |
| Outlet Capacity | 500 ML/day |
| Catchment Area | 75 km2 |
| Surface Area When Full | 10.31 km2 |
| Major Tributary | MacKenzie River |
| Average Annual Inflow | 26,000 ML/year |
| Maximum Depth | 8.2 m |
| Year Constructed | 1887 |